Nurofen (Ibuprofen) is generally useful for treating fever and pain in a wide range of ages from young children to elderly adults, provided that they do not have a bad digestive system medical history.
However in the case of chickenpox, it should NOT be used to treat a fever. Use Calpol (paracetamol) instead.
There is a change of a severe and possibly life-threatening skin reaction (known as necrotising fasciitis) to occur if ibuprofen is given for the treatment of fever in chickenpox:
SOURCES:
Shobz Pharmacy 